Effervescent solid composition of matter

ABSTRACT

An effervescent solid composition of matter is provided, which comprises, as an active component, a substance selected from chitosan, its derivatives and salts thereof and a second component capable of releasing CO 2  in an acidic environment.  
     Also, methods for treatment of a mammal suffering from a dermal wound, or for prophylactic or wound-healing treatment of lactating animals prone to develop or suffering from mastitis, are provided. The methods comprise the steps of:  
     a) admixing said effervescent solid composition of matter with an aqueous liquid to form a solution or suspension thereof;  
     b) contacting said animals with said solution or suspension to provide such treatment.

FIELD OF INVENTION

[0001] The present invention relates to solid compositions of mattercomprising an anti-microbial substance based on chitosan, itsderivatives or salts thereof. The invention also involves a method forprophylactic or wound-healing treatment of lactating animals.

BACKGROUND OF THE INVENTION

[0002] The main active principle in the solid composition of matterinvolved in the present invention is selected from chitosan, itsderivatives or salts thereof. Chitosan is a well-known polysaccharidewhich is composed of β(1-4)-linked N-acetyl-D-glucosamine andD-glucosamine units. Chitosan is manufactured by alkaline treatment ofchitin, a polymer forming the shell of inter alia insects andcrustaceans. Commercially, chitosan is recovered from crab- andshrimpshells that are waste products from the fishing industry. Whentreating chitin with alkali, usually sodium hydroxide, N-deacetylationtakes place, i e acetamido groups are converted to amino groups, as thechitin is transformed to chitosan. By controlling the alkaline treatmentof chitin it is possible to manufacture chitosans with varying degreesof N-acetylation.

[0003] Physical properties of chitosan, its derivatives and saltsthereof, which properties affect its utility, depend on the degree ofN-acetylation, the {overscore (Mw)}, the molecular weight distributionand the distribution of N-acetyl groups. Furthermore, different acidaddition salts and derivatives of chitosan exhibit different properties.

[0004] It is also known that chitosan, its derivatives and salts thereofare biologically active and inter alia show anti-microbial properties.

[0005] Chitosan and derivatives and salts thereof are used in manyforms, such as in solutions for the control of microbial growth.Examples of such solutions are solutions used as teat-dipping agents toprevent onset of mastitis in lactating cattle, as in e g WO 98/48627, aswell as solutions for other anti-microbial uses.

[0006] One problem encountered in the use of solutions of chitosan, orof derivatives or salts thereof, is lack of stability of such solutions,especially when stored at elevated temperatures.

[0007] The dissolution of chitosan, or of derivatives or salts thereof,or indeed of any polysaccharide, is often problematic when performedwithout vigorous stirring. Instead of dissolving, the polysaccharidematerial will form lumps with a gel-like shell efficiently prohibitingfurther dissolution of the material.

[0008] Furthermore, transportation of dilute solutions of chitosan, orof derivatives or salts thereof, is expensive and involves handlingproblems in preparation and use. Also, storage facilities for dilutesolutions can be costly and therefore disadvantageous.

[0009] Another possibility to solve storage and transportation problemswould be to prepare concentrated solutions. However, this is notpossible since chitosan forms very viscous solutions already at a lowconcentration, preventing the preparation of highly concentratedsolutions. Another problem with chitosan solutions, and especiallyconcentrated solutions, is that the viscosity decreases over time, dueto hydrolytic degradation.

SUMMARY OF THE INVENTION

[0010] The present invention has for a main object to provideeffervescent solid compositions of matter comprising, as an activeprinciple, a substance selected from chitosan, its derivatives and saltsthereof.

[0011] Another object of the invention is to provide such a compositionof matter, thereby avoiding transportation and storage of aqueoussolutions or suspensions of the active principle, since such solutionsor suspensions can be easily prepared by the consumer at the time ofuse.

[0012] Yet another object of the invention is to provide suchcompositions of matter, which are stable in storage for a prolonged timebefore use thereof.

[0013] A further object of the invention is to provide solidcompositions of matter comprising a substance selected from chitosan,its derivatives and salts thereof, which substances are otherwise notreadily dissolved or suspended, which compositions are readily dissolvedor suspended in aqueous liquid.

[0014] Still another object of the invention is to provide effervescentsolid compositions of matter comprising, in addition to a substanceselected from chitosan, its derivatives and salts thereof, a substanceselected from heparin, heparan sulfate, dextran sulfate and othernegatively charged polysaccharides or polymers.

[0015] A further object of the invention is to provide solidcompositions of matter, such that solutions or suspensions made thereof,when used as teat-dipping agents, upon drying will form films on theareas treated.

[0016] Another object of the present invention is the provision ofmethods for wound-healing treatment of mammals.

[0017] Still another object of the invention is to provide a method forprophylactic or wound-healing treatment of lactating animals prone todevelop or suffering from mastitis, particularly cows.

[0018] For these and other objects which will be evident from thefollowing disclosure, the present invention provides an effervescentsolid composition of matter comprising as an active component asubstance selected from chitosan, its derivatives and salts thereof anda second component capable of releasing CO₂ in an acidic environment.

[0019] The composition of matter according to the invention preferablycontains less chitosan, or derivative or salt thereof, than 50% byweight of chitosan, more preferably less than 25% by weight of chitosan.In keeping with the objects of the invention, this preferred proportionof chitosan, or derivative or salt thereof, in the composition of matteris mainly dictated by the capacity for dissolution or suspension of theactive ingredient by the second component and the acidic environment,when the composition is placed in an aqueous liquid. The content ofchitosan, or of derivatives or salts thereof, has to be sufficientlylow, compared to the content of effervescing components in thecomposition of matter, for dissolution to occur. The percentage referredto above is thus the percentage of chitosan in relation to effervescingcomponents. Surprisingly, it has been found by the present inventorsthat the relation between the quantity of effervescence-generatingcomponents and chitosan, or derivatives or salts thereof, is criticalfor the dissolution of the composition in an aqueous liquid. As statedabove, most chitosan qualities will not dissolve without vigorousstirring, even in large amounts of aqueous liquid and after long times.This also holds true if the proportion of chitosan is too large inrelation to the quantity of effervescing components. The dissolutionrate of chitosan, or derivatives or salts thereof, in the composition ofmatter according to the invention thus depends on efficient mixingcaused by release of CO₂ from the effervescent components, as well as onthe final pH of the solution, as described in detail below.

[0020] If chitosan derivatives or salts are used that are more easilydissolved than chitosan itself, the percentage thereof may be increased.The same is true for chitosan, or derivatives or salts thereof, ofdifferent molecular weights, low-molecular weight qualities being moreeasily dissolved or suspended.

[0021] The preferred quality of the chitosan, or derivative or saltthereof, used in the composition of matter according to the inventiondepends on the specific area of use. This in turn will influence theconcentration of chitosan, or derivative or salt thereof, that ispreferred.

[0022] To obtain maximum anti-microbial efficiency, in those embodimentsof the invention where this is desired, it is preferred that thechitosan, or derivative or salt thereof, has a degree of deacetylationof no less than about 50%, preferably no less than about 80% andparticularly no less than about 85%. However, an upper limit of thedeacetylation degree of about 95% is preferred, mainly due to practicaland economic aspects of the preparation of chitosan, or derivative orsalt thereof. Thus, a preferred composition of matter according to theinvention comprises chitosan, or derivative or salt thereof, having adeacetylation degree within the range from about 85% to about 95%, butthe upper limit of 95% may be exceeded by compositions that still comewithin the scope of the present invention. This may occur for example ifan economical process of obtaining chitosan of such high degree ofdeacetylation is made available. Then, chitosan having a deacetylationdegree of up to 99% or more may be obtainable, and may well be used incompositions according to the present invention.

[0023] The viscosity of an aqueous solution of a certain concentrationof chitosan, or derivative or salt thereof, can be modified by usingqualities of chitosan, its derivatives or salts thereof with differentweight average molecular weights ({overscore (Mw)}), In the presentinvention, chitosan, or derivative or salt thereof, with a molecularweight of between 1 kDa and 2000 kDa is preferred.

[0024] The preferred particle size of the chitosan, or derivative orsalt thereof, used is less than 850 μm, more preferably less than 250 μm(60 mesh). If chitosan, or derivative or salt thereof, of anotherparticle size is used, ox if the molecular weight of the chitosan, orderivative or salt thereof, is such that dissolution of particles isdifficult, the particles may be ground to a smaller size prior to use.

[0025] In a composition of matter according to the invention, saidsecond component is preferably a carbonate, e g selected from alkalimetal carbonates, alkali metal bicarbonates, alkaline earth metalcarbonates, alkaline earth metal bicarbonates, ammonium carbonate, andammonium bicarbonate.

[0026] Said second component has the capacity to release CO₂ in anacidic environment. This acidic environment may be provided as anaqueous solution with a low pH, e g an acetic acid solution, in whichthe composition of matter is placed, In preferred embodiments, however,release of CO₂ is obtained through the use of a third component of thesolid composition, which is selected from solid acids and mixturesthereof.

[0027] In such embodiments, said second and third component of thecomposition of matter according to the invention can be regarded as an“effervescent couple”. The effervescent couple thus comprises at leastone component capable of releasing CO₂ in an acidic environment (thesecond component of the composition of matter) and at least one solidacid (the third component), preferably a solid organic acid. The couplerenders effervescence upon mixing with an aqueous solution, as thecomponents of the couple combine to produce carbon dioxide. Theeffervescing action also aids in mixing the other ingredients of thecomposition to achieve even dispersion and solubilisation throughout thesolution.

[0028] In those embodiments of the invention that employ a solid acid,or mixture of solid acids, as a third component, it is preferred to usea solid organic acid, or mixtures of solid acids comprising at least onesolid organic acid. Preferably, this is a weak organic acid thatprovides a certain buffering effect resulting in a less varying pH in asolution or suspension prepared by dissolution or suspension of thesolid composition according to the invention. For the purposes ofpreparing a solution or suspension for use on the teats of lactatinganimals, a non-toxic, mono-carboxylic acid, e g a non-toxic α-hydroxyacid, is preferred, glycolic acid being the most preferred for thisapplication, In other applications, the preferred solid organic acid maybe an α-hydroxy acid or an acid other than a-hydroxy acids, includingascorbic acid. In most biological applications, the solid acid will needto exhibit properties such as non-toxicity and pharmaceuticalacceptability. The pK_(a) of the solid acid is preferably below 7, apK_(a) below 5 being even more preferred.

[0029] A particularly preferred composition of matter according to theinvention is constituted by the active component being selected fromchitosan, its derivatives and salts thereof, the second component beingan alkali metal bicarbonate, and the composition further comprising athird component which is glycolic acid.

[0030] In the composition of matter according to the invention, thecontents of acid thereof is preferably in stoichiometric excess over thecontents of said second component.

[0031] Where the active component is an acid addition salt of chitosanand the composition contains a solid acid, or mixture of solid acids, asthird component, said stoichiometric excess is based on said thirdcomponent together with the acid of addition.

[0032] Where the composition of matter according to the inventioncontains chitosan as such as active principle and a solid acid, ormixture of solid acids, as third component, said stoichiometric excessrefers to the contents of the third component over the second component.

[0033] The composition of matter, according to those embodiments of theinvention that contain a solid acid, or mixture of solid acids, as thirdcomponent, preferably has an acid content such that, when thecomposition is dissolved or suspended in the appropriate amount ofaqueous liquid, the pH of the solution or suspension is below about 7,so that the chitosan of the composition is readily dissolved. Morepreferably, the pH value is in the range of from about 2 to about 6.8,the lower limit being dictated mainly by the desired properties of thesolution or suspension. For applications wherein the solution orsuspension is to be applied to the skin of an animal or human subject,the pH range is even more preferably from about 4 to about 6.8, thelower limit here being dictated by the sensitivity of the area to whichthe solution or suspension is to be applied.

[0034] When the composition is dissolved or suspended in the appropriateamount of liquid, the pH of the solution or suspension can optionally befurther stabilised by use of a pH buffering system, which in certainapplications of the present invention will need to be non-toxic andpharmaceutically acceptable. Examples of preferred buffering systemsinclude the acetic acid system and buffer systems of other monovalentacids, e g lactic acid.

[0035] The acidic pH of the liquid provides a suitable environment fordissolution or suspension of chitosan, or of a derivative or saltthereof, as well as a suitable environment for CO₂ release from thesecond component. Inventively, these two effects operate in asynergistic manner to facilitate the dissolution or suspension ofchitosan, or derivative or salt thereof, in the liquid.

[0036] The composition of matter according to the invention mayadditionally contain heparin, heparan sulfate, dextran sulfate oranother negatively charged polysaccharide or polymer. It may also bepreferred to include neutral polymers, e g cellulose, in the compositionof matter according to the invention, since such polymers may conferdesired properties to a solution or suspension made from thecomposition, in terms of e g improved clarity or viscosity.

[0037] The composition of matter according to the present invention canbe presented in different forms, e g powder, granules, pellets, capsulesor tablets of suitable size, prepared by standard methods well known tothe skilled person. An additional component of the composition, e g anyof the negatively charged polysaccharides mentioned in the previousparagraph, may be added as a separated coating around a core consistingof the main components of the composition of matter, forming a dragée,or as a part of a tablet containing more than one compartment.

[0038] The composition of matter according to the present invention mayoptionally further comprise pharmaceutically acceptable excipients knownto the skilled person, e g binders, diluents, surfactants, lubricants,disintegrants, anti-microbial agents, detergents and colouring agents.

[0039] The composition of matter according to the present invention ispreferably kept in moisture-proof or airtight packages or containers, eg welded aluminum containers, etc. Transportation of products in a dryform and in moisture-proof packets makes it more difficult tocontaminate the product. Further, such compositions are much lessexpensive to transport than compositions in liquid form. In many cases,the effectiveness of active ingredients is prolonged in a dry, ratherthan liquid, state due to increased stability of the ingredients in thedry state.

[0040] The composition of matter according to the invention is thusespecially practical when it is used for the preparation of solutions orsuspensions, which retain their activity for only a short time afterpreparation thereof, since said solutions or suspensions may be preparedshortly or even immediately before use,

[0041] According to one preferred embodiment, the composition of matteraccording to the present invention is kept in one separate,moisture-proof container, while an effervescent composition of mattercomprising heparin, heparan sulfate, dextran sulfate or anothernegatively charged polysaccharide or polymer is kept in another separatecontainer. Thus, the contents of the two containers may be usedsimultaneously or at separate instants. Another possibility is theprovision, in such a second, separate container, of a liquid, e gglycerol, that confers desired properties, e g a skin conditioningeffect, to the resulting solution or suspension.

[0042] The composition of matter according to the present invention canbe used as a medicament. In particular, the composition of matteraccording to the present invention can be used for the manufacture of anaqueous solution or suspension for treatment of dermal wounds in mammalsincluding man. Furthermore, the composition of matter according to thepresent invention can advantageously be used for the manufacture of anaqueous solution or suspension for prophylactic or wound-healingtreatment of mastitis in lactating animals.

[0043] The present invention also relates to a method for treatment of amammal suffering from a dermal wound, which method comprises the stepsof:

[0044] a) admixing an effervescent solid composition of matter accordingto the present invention with an aqueous liquid to form a solution orsuspension thereof;

[0045] b) contacting the dermal wound of said mammal with said solutionor suspension to provide such treatment.

[0046] The present invention also relates to a method for prophylacticor wound-healing treatment, or both, of a lactating animal prone todevelop or suffering from mastitis. The method comprises the steps of:

[0047] a) admixing an effervescent solid composition of matter accordingto the present invention with an aqueous liquid to form a solution orsuspension thereof;

[0048] b) contacting teats of said animal with said solution orsuspension to provide such treatment.

[0049] The methods according to the invention, described immediatelyabove and having regard to mastitis, suitably take place in connectionwith milking operations. Considering the daily milking, the applicationis suitably performed twice or thrice a day after milking. In certaincases it may be preferable to apply the solution before milking,considering the risk of transferring microorganisms during the milkingprocess. The method of the invention is very well suited for such apre-milking treatment, as the risk of transferring non-desirablecomponents into the milk is minimized through the use of achitosan-containing solution or suspension. Chitosan, or derivative orsalt thereof, is preferably present in the solution or suspension in ananti-microbial active concentration.

[0050] Preferably, in the methods of the invention, an effervescentcomposition of matter is used which comprises components that provide askin conditioning effect on skin. Such components may be glycolic acidas the third component, or glycerol as an additive, but other skinconditioning components are possible.

[0051] In such methods it is preferred that said composition of matteris used in an amount resulting in a solution or suspension having aconcentration of chitosan of up to and including about 2%(weight/volume), the upper limit being mainly dictated by economic andpractical considerations, The most preferable concentration of chitosanin said solution or suspension is about 1% (w/v).

[0052] A particularly preferred composition of matter for use in themethods for prophylactic or wound-healing treatment according to theinvention comprises a combination of chitosan, or derivative or saltthereof, and one or more of the additional substances heparin, heparansulfate and dextran sulfate, whereby solutions or suspensions madethereof when used as teat-dipping agents upon drying will formparticularly water-resistant films on the areas treated.

[0053] Other applications of use for the composition of matter accordingto the invention than that of the methods described above are possible.In such applications, solutions or suspensions having even lowerconcentrations, e g down to about 0.1% (w/v) of chitosan, may proveactive and effective. In such cases, lower concentrations naturallyoffer advantages in terms of economy.

[0054] Examples of Preferred Embodiments

[0055] The present invention will in the following be illustrated inconnection with non-limiting examples. In said examples parts andpercentages refer to weight if not otherwise stated.

[0056] Compositions with other dissolution times than those reported caneasily be prepared by changing the ratio between chitosan, or derivativeor salt thereof, and effervescent couple. The form of the composition ofmatter, e g powder, granules, pellets, capsules or tablets, will alsoaffect the dissolution time. Also, the pressure applied when preparingtablets affects the dissolution time of a resulting tablet.

[0057] Materials

[0058] The chitosan used in the following examples was of commercialgrade, having a deacetylation degree of 84-99%. Likewise, the heparinused was of commercial grade.

[0059] TABLET EXPERIMENT—EXAMPLES 1-5

[0060] Preparation of Tablets

[0061] The tablets of the examples below were prepared in laboratoryscale by mixing and grinding of the included chemicals into fineparticles. For compression of standard size tablets, a standard FTIRpress was used. Larger tablets were compressed in a specially adaptedpress made from a plastic tube with a lid and bottom. Materials weretransferred into the tube and the lid fitted. The device was then placedin a press designed for production of FTIR tablets, whereupon thematerials were compressed at approximately 3 tons for 30-60 seconds.

[0062] The tablets of the examples below had diameters in the range fromabout 13 to about 40 mm, with thicknesses of about 2, 3 or 7 mm,depending on the amount of material present in the tablet.

[0063] Dissolution times refer to solutions that are not stirred duringdissolution of tablets.

EXAMPLE 1

[0064] The compositions of Table 1 were prepared by mixing chitosan oran acid addition salt thereof with a solid acid and sodium bicarbonate.solid preparations of powder or tablets were formed as described above,TABLE 1 Sodium Compo- Chitosan Chitosan · HCl bicar- sition (g) (g) Acidbonate (g) A 1.0 2.0 g glycolic acid 2.0 B 1.0 2.2 g glycolic acid 2.0 C1.0 1.6 g benzoic acid 1.0 D 1.0 1.8 g salicylic acid 1.0 E 1.0 5.6 gascorbic acid 2.4 F 1.0  20 g citric acid 1.8 G 3.0 3.0 g glycolic acid3.0 H 1.0 2.0 g glycolic acid 1.8 J 0.5 1.0 g glycolic acid 0.9 K 2.04.0 g glycolic acid 3.5 L 1.0 2.3 g glycolic acid 2.0

EXAMPLE 2

[0065] The solid compositions A-F of Table 1 were admixed with 100 mltap water at ambient temperature. The solid composition G of Table 1 wasadmixed with 300 ml tap water at ambient temperature. Thus, chitosan orits acid addition salt was added in an amount corresponding to 1.0%(weight/volume) of the total volume. The time from addition of thecomposition until it was fully dissolved was recorded and is shown Table2, as is the pH value of each resultant solution. TABLE 2 Composition pHDissolution time (h) A 4.7 1   B 5.5 0.8 C 3.2 over night^(a) D 4.9 overnight^(a) E 5.1 5^(b) F 2.3  0.03 G 4.7 5.5

EXAMPLE 3

[0066] The solid compositions H-K of Table 1 were admixed with 100 mltap water at ambient temperature. Thus, chitosan was added in an amountcorresponding to from 0.5% to 2.0% (w/v) of the total volume. The timefrom addition of the composition until it was fully dissolved wasrecorded and is shown in Table 3, as is the pH value of each resultantsolution. TABLE 3 Composition % Chitosan pH Dissolution time (h) H 1.05.3-5.5 0.8 J 0.5 5.5-5.8 0.2 K 2.0 5.3-5.4 1.5

EXAMPLE 4

[0067] A tablet was prepared containing 0.02 g heparin, 0.1 g glycolicacid, and 0.1 g sodium bicarbonate. The tablet was dissolved in 100 mltap water at ambient temperature. The solid composition L of Table 1 wasadmixed with the solution.

[0068] Thus, chitosan was added in an amount corresponding to 1.0% (w/v)of the total volume. The time from addition of the composition until itwas fully dissolved was approximately 45 minutes. The resulting solutioncontained 1.0% (w/v) chitosan and 0.02% (w/v) heparin, pH 5.0.

EXAMPLE 5

[0069] A tablet was prepared containing 1.0 g chitosan and 1.75 g sodiumbicarbonate. The tablet was dissolved in 100 ml of a solution of 6%acetic acid at ambient temperature.

[0070] The tablet was completely dissolved in approximately 10 minutes.

[0071] GRANULATION EXPERIMENT—EXAMPLES 6-17

[0072] In all of the examples below, chitosan granulate is added towater in an amount yielding solutions of 1% by weight of chitosan. Inthose-cases (examples 12-17) where heparin is added to water, the amountthereof corresponds to 0.02% by weight in the final solutions.

EXAMPLE 6

[0073] 100.3 g chitosan, 198.0 g glycolic acid and 175.3 g NaHCO₃ weremixed for one minute in a Kenwood mixer, and granulated with 21.5 g ofan aqueous solution of ethanol (70%). The granulate was dried in aheating cabinet for 4 h at 50° C., and then sieved through a 1.3 mm handsieve. Finally, the granulate was mixed for 40 minutes in a Turbulamixer.

[0074] When 4.7 g of the granulate was dissolved in 100 ml of water, ayellow solution was obtained. With stirring, the granulate was dissolvedwithin 30 seconds. Some foaming occurred.

EXAMPLE 7

[0075] 49.9 g chitosan and 99.3 g glycolic acid were mixed for oneminute in a Kenwood mixer, and granulated with about 9 g of an aqueoussolution of ethanol (70%). The granulate was dried in a heating cabinetfor 3 h at 50° C., and then sieved through a 1.3 mm hand sieve. 87.8 gNaHCO₃ was added, and the final granulate was mixed for 20 minutes in aTurbula mixer.

[0076] The granulate exhibited a strong effervescent reaction when mixedwith water, dissolving in a clear, slightly yellow solution.

EXAMPLE 8

[0077] 50.0 g chitosan and 88 g NaHCO₃ were mixed in a Turbula mixer for10 minutes. 99.3 g glycolic acid were added, and the mixing wascontinued for another 10 minutes. Subsequently, the mixture was sievedthrough a 1.3 mm sieve.

[0078] The granulate was relatively easily dissolved in water, and aslightly yellow and not completely clear solution was obtained.

EXAMPLE 9

[0079] 49.6 g chitosan, 50.1 g lactose, 99.7 g glycolic acid and 87.8 gNaHCO₃ were granulated with 17 g of an aqueous solution of ethanol (70%)in a Kenwood mixer. The resulting granulate was dried for 4 h at 50° C.in a drying cabinet. Finally, the granulate was sieved through a 1.3 mmsieve.

[0080] When enough granulate was added to water to form a 1% chitosansolution, part of the granulate floated on the surface of the water, andit was necessary to aid dissolution by stirring.

EXAMPLE 10

[0081] 100 g chitosan and 150 g lactose were granulated with 100 g of anaqueous povidone solution (10%) in a Kenwood mixer. The granulate wasdried for 2.5 h at 50° C. in a drying cabinet, before being sievedthrough a 1.5 mm sieve.

[0082] 50 g of the resulting granulate, 45 g glycolic acid and 35 gNaHCO₃ were then mixed in a Turbula mixer for 10 minutes. 6.5 g of themixture was added to 100 ml of water, giving a solution of 1% by weightchitosan. The granulate dissolved fast during intensive foaming whenstirred, giving an almost clear solution with a pH of 3.7.

EXAMPLE 11

[0083] 50 g chitosan, 100 g lactose and 120 g glycolic acid weregranulated with 72 g of an aqueous solution of ethanol (70%) in aKenwood mixer. The granulate was dried for 4 h at 50° C. in a drivingcabinet, before being sieved through a coarse sieve.

[0084] 5.4 g of the resulting granulate was mixed with 1.7 g NaHCO₃.When placed in water, this mixture was relatively easily dissolved. Someof the material sunk to the bottom of the vessel, and a calmeffervescent reaction started. All of the material was dissolved afterone hour, yielding a solution with a pH of 4.4. After 24 h the solutionwas totally clear and the pH value 4.24.

EXAMPLES 12-17

[0085] Preparation of Heparin Granules:

[0086] 2.00 g heparin and 10.0 g lactose were mixed with a spoon. 2 g ofan aqueous povidone solution (20%) was added as granulation liquidduring stirring using a nozzle. The resulting granulate was dried for 2h at 60° C. in a drying cabinet and then sieved through a 1.5 mm sieve,yielding a fine white-grey powder.

[0087] Preparation of Chitosan Granules:

[0088] 50 g chitosan, 100 g lactose and 120 g glycolic acid weregranulated with 72 g of an aqueous solution of ethanol (70%) in aKenwood mixer. The granulate was dried for 4 h at 50° C. in a dryingcabinet, before being sieved through a coarse sieve.

[0089] Preparation of Chitosan-heparin Solutions:

[0090] In examples 12-17, 0.12 g of the heparin granulate obtained abovewas placed in 100 ml of distilled water at a temperature of 22° C. pHmeasurements were used to monitor the dissolution process. Next, thechitosan granulate obtained above was added. In examples 12, 14 and 16,the chitosan granulate was mixed with NaHCO₃ prior to addition of thepowder to the heparin solution. In examples 13, 15 and 17, the NaCHO₃was added separately a few seconds after the addition of chitosan to theheparin solution.

[0091] The results are shown in Table 4 below. In all examples, thematerial was totally dissolved, yielding solutions of 0.02% by weight ofheparin and 1% by weight of chitosan. TABLE 4 Heparin granulate pH pH ofChitosan (minutes heparin granulate NaHCO₃ after Example (g) solution(g) (g) Addition addition) 12 0.12 6.8 5.4 1.7 Mixed dry with 5.4 (30)the chitosan granulate 13 0.12 7.7 5.4 1.7 Separately 4.3 (45) 14 0.12 —5.4 1.5 Mixed dry with 4.7 (—) the chitosan granulate 15 0.12 6.7 5.41.7 Separately 4.1 (90) 16 0.12 6.9 5.4 2.1 Mixed dry with 5.2 (90) thechitosan granulate 17 0.12 7.2 5.4 2.1 Separately 5.5 (90)

1. An effervescent solid composition of matter comprising, as an activecomponent, a substance selected from chitosan, its derivatives and saltsthereof and a second component capable of releasing CO₂ in an acidicenvironment.
 2. A composition of matter according to claim 1, whichfurther comprises a third component selected from solid acids andmixtures thereof.
 3. A composition of matter according to any one ofclaims 1 and 2, wherein said active component is a salt of chitosan. 4.A composition of matter according to any one of claims 1 and 2, whereinsaid active component is chitosan.
 5. A composition according to anypreceding claim, additionally containing heparin, heparan sulfate,dextran sulfate or another negatively charged polysaccharide or polymer.6. A composition of matter according to any preceding claim, whereinsaid second component is a carbonate.
 7. A composition of matteraccording to claim 6, wherein said carbonate is selected from alkalimetal carbonates, alkali metal bicarbonates, alkaline earth metalcarbonates, alkaline earth metal bicarbonates, ammonium carbonate, andammonium bicarbonate.
 8. A composition of matter according to any one ofclaims 2-7, wherein the acid content in the composition of matter issuch that the pH of a solution or suspension made thereof is below about7.
 9. A composition of matter according to any one of claims 2-8,wherein the acid content in the composition of matter is such that thepH of a solution or suspension made thereof is in the range from about 2to about 6.8.
 10. A composition of matter according to any one of claims2-9, wherein the acid content in the composition of matter is such thatthe pH of a solution or suspension made thereof is in the range fromabout 4 to about 6.8.
 11. A composition of matter according to any oneof claims 2-10, wherein the acid content, originating from said thirdcomponent plus any acid addition salt of chitosan, is in stoichiometricexcess over said second component.
 12. A composition of matter accordingto any one of claims 2-11, wherein said third component is selected fromorganic solid acids and mixtures thereof.
 13. A composition of matteraccording to claim 12, wherein said third component is selected fromα-hydroxy acids.
 14. A composition of matter according to claim 13,wherein said third component is glycolic acid.
 15. A composition ofmatter according to any one of claims 2-14, wherein said activecomponent is a substance selected from chitosan, its derivatives andsalts thereof, said second component is an alkali metal bicarbonate, andsaid third component is glycolic acid.
 16. A composition of matteraccording to any preceding claim in the form of powder, granules,pellets, capsules or tablets.
 17. An effervescent solid composition ofmatter according to any preceding claim for use as a medicament.
 18. Theuse of an effervescent solid composition of matter according to any oneof claims 1-16 for the manufacture of an aqueous solution or suspensionfor treatment of dermal wounds in mammals.
 19. The use of aneffervescent solid composition of matter according to any one of claims1-16 for the manufacture of an aqueous solution or suspension forwound-healing treatment of mastitis in lactating animals.
 20. The use ofan effervescent solid composition of matter according to any one ofclaims 1-16 for the manufacture of an aqueous solution or suspension forprophylactic treatment of mastitis in lactating animals.
 21. A methodfor treatment of a mammal suffering from a dermal wound, comprising thesteps of: a) admixing an effervescent solid composition of matteraccording to any one of claims 1-16 with an aqueous liquid to form asolution or suspension thereof; b) contacting the dermal wound of saidmammal with said solution or suspension to provide such treatment.
 22. Amethod for wound-healing treatment of a lactating animal suffering frommastitis, comprising the steps of: a) admixing an effervescent solidcomposition of matter according to any one of claims 1 to 16 with anaqueous liquid to form a solution or suspension thereof; b) contactingteats of said animal with said solution or suspension to provide suchtreatment.
 23. A method for prophylactic treatment of a lactating animalprone to develop mastitis, comprising the steps of: a) admixing aneffervescent solid composition of matter according to any one of claims1 to 16 with an aqueous liquid to form a solution or suspension thereof;b) contacting teats of said animal with said solution or suspension toprovide such treatment.
 24. A method according to any one of claims21-23, wherein said composition of matter is used in an amount resultingin a solution or suspension having a concentration of chitosan of up toabout 2% by weight.
 25. A method according to any one of claims 21-24,wherein said composition of matter is used in an amount resulting in asolution or suspension having a concentration of chitosan of about 1% byweight.